Translating apparatus



Nov. 25, 1952 E. T. OLIVER TRANSLATING- APPARATUS ll Sheets-Sheet 1Filed July 21, 1951 f S 8 4 m f 0 F 2 Z n V. W 2;. m w l T. A Y\\Q mm oa 4 mb E I m 3 h v. 7 4 w M 7 I U y w H 2 H w 8 M 4 m; m. w J}.

NJ o .m. II 2 Nov. 25, 1952 OLIVER 2,618,984

TRANSLATING APPARATUS Filed July 21, 1951 ll Sheets-Sheet 2 [u] I Q I20u In van/0r E merson 7'. 0/! var Attorneys NOV. 1952 I E. T. OLIVER2,613 98 Filed July 21, 1951 11 Sheets-Sheet s TRANSLATING APPARATUSInventor Emerson 7'. Oliver Y/Zd- M KW Attorneys 1952 E. T. OLIVERTRANSLATING APPARATUS ll Sheets-Sheet 4 Filed July 21, 1951 InventorEmerson 7'. Oliver b y Maw A fforneys Nov. 25; 1952 E. T. OLIVER2,618,984

TRANSLATING APPARATUS Filed July 21, 1951 ll Sheets-Sheet 5 k 301' 72flora; l/9ar83 I a I 0 cl 0 l B \m Fig. /6.

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Inventor Emerson 71 Oliver byfluil dual Afrorneys 1952 E. T. OLIVERTRANSLATING APPARATUS ll Sheets-Shet 6 Filed July 21, 1951 lnvenforEmerson 7'. Oliver b Af/orneys Nov. 25, 1952 E. T. OLIVER TRANSLATINGAPPARATUS 11 Sheets-Sheet 7 Filed July 21, 1951 Inventor 200 202 MALbyflzuad/ A lforneys Emerson 7'. Oliver I Fig. 22.

Nov. 25, 1952 E. T. OLIVER TRANSLATING APPARATUS ll Sheets-Sheet 8 FiledJuly 21, 1951 lnvenfor Emerson I Oliver Attorneys m9 mm Nov. 25, 1952 E.T. OLIVER TRANSLATING APPARATUS ll Sheets-Sheet 9 Filed July 21, 1951Inventor Emerson T. Oliver b flauaw Attorneys Nov. 25, 1952 E. T. OLIVER2,618,984

TRANSLATING APPARATUS Filed July 21, 1951 ll Sheets-Sheet ll 2 270r/5A22 I I I I l o-(-e) M Inventor Emerson 7T Oliver A Nor/lays PatentedNov. 25, 1952 UNITED STATES PATENT OFFICE 51 Claims.

The present invention relates to translating apparatus, and moreparticularly to apparatus for increasing and decreasing speed. From amore specific aspect, the invention relates to apparatus fortransmitting power from a highspeed to a low-speed or from a low-speedto a high-speed shaft. This application is a continuation-in-part ofapplication, Serial No. 752,703, filed June 5, 1947.

An object of the invention is to provide a new and improved translatingapparatus for effecting speed variation between alined high-speed andlow-speed shafts.

Another object i to provide a new and improved speed reducer.

A further object is to provide a new and improved speed-increasingmechanism.

Other and further objects will be explained hereinafter and will be moreparticularly pointed out in the appended claims.

One of the alined high-speed and low-speed :shafts may be regarded asthe control shaft and the other as the controlled shaft. In the case ofspeed reduction, for example, the high-speed :shaft may be regarded asthe control shaft and the low-speed as the controlled shaft. In the caseof speed increase, on the other hand, the Slow-speed shaft may beregarded as the control shaft and the high-speed shaft as the controlled:shaft.

The invention comprises meshing circular gears -'one of which,concentric with the common axis of the alined shafts, is stationary, andthe other ='of which is fixed to the control shaft in order that fit maytravel in a circular orbit about the common :axis of the alined shafts.This other member may therefore be referred to as a control member. .Athird member, which may be referred to as the controlled member, isfixed to the controlled shaft. If the control member is fixed to thehigh-speed shaft, for example, the controlled member is fixed to thelow-speed shaft; and if the control member is fixed to the low-speedshaft, the controlled memberis fixed to the highspeed shaft. During itstravel in the said orbit, the control member rotates about its Own axis,thus maintaining its circular periphery in engagement with the circularperiphery of the concentrically disposed member.

The control member is provided with a projection which thereforedescribes a hypotrochoidal or epitrochoidal path intersecting the commonaxis of the alined shafts. Whether the path is hypotrochoidal orepitrochoidal depends upon whether the fixed projection is inside oroutside the circumference of the control member to which it is fixed.This projection, which may be referred to as a control projection,because it is part of the control member, is slidably connected to thecontrolled member that is fixed to the controlled shaft.

The controlled member is provided with a straight guide slot that issymmetrically disposed with respect to the common axis of the alinedshafts, so that the center of the guide slot is disposed on the commonaxis of the alined shafts. The slidable connection of the controlprojection to the controlled member is brought about by slidablymounting the control projection in the guide slot. The control.projection therefore oscillates back and forth in the guide slot alongits hypotrochoidal or epitrochoidal path, passing through the center ofthe guide slot each time that it oscillates from one end of the guideslot to the other end. The control member thus maintains control overthe controlled member through the engagement of the control projectionwith the walls of the guide slot.

At the moment when it passes through the center of the guide slot,however, the control projection occupies a position of deadcenter. Inorder that, in this position of dead center, the control projectionshall not lose its control over the controlled member, it is preferredto employ two such control projections, respectively mounted in twostraight guide slots of the abovedescribed character, these guide slotsbeing disposed at right angles to each other. The invention may,however, be employed with only one such control projection or with morethan two such control projections.

Another object of the present invention is to vary the speed reductionor increase. To the attainment of this end, a feature of the inventionresides in adjusting the length of the circumference of one or the otherof the circular gears, or both. According to a further feature of theinvention, as herein illustrated and described, this adjustment may beeffected at will, during the operation of the machine. I

The invention Will now be more fully explained in connection with theaccompanying drawings, in which Fig. l is a vertical section, taken uponthe line l-l of Fig. 2, looking in the direction of the arrows, of aspeed-reducer constructed in accordance with the present invention; Fig.2 is a horizontal section taken upon the line 22 of Fig. 1, looking inthe direction of the arrows; Fig. 3 is a perspective, partly in sectionupon the line 3-3 and partly in section upon the line 2-2 of Fig. 1,looking in the directions of the respective arrows, with parts brokenaway, for clearness, and with the parts occupying relatively differentpositions; Fig. 4 is a section taken upon the line 44 of Fig. 6, lookingin the direction of the arrows, but upon a larger scale; Fig. 5 is asection taken upon the 1ine 5-5 of Fig. 4, looking in the direction ofthe arrows; Fig. 6 is a view similar to Fig. 1, of a modification, butupon a smaller scale; Figs. 7 to 11, inclusive, are views similar toFig. 6, illustrating successive steps in the operation; Fig. 12 is asection taken upon the line I2l2 of Fig. 2, looking in the direction ofthe arrows; Fig. 13 is an end elevation, looking from the right of Fig.12; Fig. 14 is a diagram explanatory of the mathematical theoryunderlying one form of the invention; Figs. 15 to 18, inclusive, areviews similar to Fig. 14, showing diagrammatically successive branchesof a hypotrochoidal path traced by the point P of Fig. 14; Fig. 19 is avertical section similar to Fig. 1, taken upon the line I9l9 of Fig. 20,looking in the direction of the arrows, of a further modification; Fig.20 is a horizontal section similar to Fig. 2, taken upon the line 2828of Fig. 19, looking in the direction of the arrows; Fig. 21 is avertical section similar to Figs. 1 and 19, taken upon the line 2I-2I ofFig. 24, looking in the direction of the arrows, of anothermodification; Fig. 22 is a fragmentary perspective of the modificationshown in Figs. 21 and 24, partly in sec tion upon the line 22-22 of Fig.24, looking in the direction of the arrows; Fig. '23 is a section takenupon the line 23-43 of Fig. 21, looking in the direction of the arrows;Fig. 24 is a horizontal section similar to Figs. 2 and 20, taken uponthe line 24-24 of Fig. 21, looking in the direction of the arrows, butupon a larger scale; Fig. '25 is a vertical section similar to Figs. 1,19 and 21, taken upon the line 25-45 of Fig. 26, looking in thedirection of the arrows, of still another modification; Fig. 26 is ahorizontal sec tion similar to Figs. 2, 20 and 24, taken upon the line26--26 of Fig. 25, looking in the direction of the arrows; Fig. 2'7 is avertical section similar to Figs. 1, 19, 21 and 25, taken upon the line2'I2I of Fig. 28, looking in the direction of the arrows, of amodification for increasing speed in accordance with the presentinvention; Fig. 28 is a horizontal section similar to Figs. 2, 20, 24and 26, taken upon the line 23-28 of Fig. 2'7, looking in the directionof the arrows; Fig. 29 is a diagram similar to Fig. 14, but applicableto the form of the invention that is illustrated in Figs. 19 to 24,inclusive; Fig. 30 is a diagram similar to Figs. 14 and 29, butapplicable to the form of the invention that is illusrated in Figs. 27and 28; and Fig. 31 is a reproduction of a portion of the diagram ofFig. 14, upon a larger scale, in a setting of Cartesian coordinate axesX and Y, with additional symbols explanatory of the mathematical theory.

The invention is illustrated in Figs. 1 to 26, 29 and 31, as applied tospeed reduction between alined high-speed and low-speed shafts, and inFigs. 27, 28 and 30 as applied to increasing, instead of decreasing, thespeed.

The high-speed shaft is shown at 5 and the low-speed shaft at I! in theembodiments of the invention shown by Figs. 1 to 18 and 31, inclusive;at or 24 and at 35, respectively, in the embodiment of the inventionshown by Figs. 19 and 20; at I55 and I83, respectively, in theembodiment of the invention illustrated by Figs. 21 to 24, inclusive; at15 and 89, respectively, in th em.-

bodiment of the invention illustrated by Figs. 25 and 26; and at H4 andI05, respectively, in the embodiment of the invention illustrated byFigs. 27, 28 and 30.

In the embodiment of the invention illustrated by Figs. 1 to 18 and 31,the high-speed shaft 5 is shown journaled in a bearing 6 of a half-shellI, and the alined low-speed shaft I! is shown journaled in a bearing I8of a half-shell 2. The half-shells I and 2 are shown secured together bybolts 4 to provide a closed container for the speed-reducing mechanism.The corresponding journal bearings for the high-speed shafts 49 or 24,I55, I5 and H4 are shown in Figs. 20, 24, 26 and 28, respectively, at23, I59, 74 and 97, respectively mounted in the half-shells I9, I5I, Itand 95, and the corresponding journals for the respective low-speedshafts 35, I83, 89 and IE5 at 36, 68, 90 and 93, respectively mounted inthe half-shells 20, I52, II and 94.

In practice, the bearings 5 and I8 may be of the tapered-roller type,with a loaded thrust, but they are shown of a more simple type, forsimplicity. The bearings are held securely in place by thrust collars 42that are secured to the highspeed and the low-speed shafts by pins 43extending through the collars -42 and the shaft, with a ball-bearing orwasher M interposed.

Held stationary in the closed container of Figs. 1 to 11 by the bolts 4,between the half-shells I and 2, is an internal circular gear member 3having internally disposed gear teeth. I The internal circular gearmember 3,is concentric with the axis of the alined high-speed andlow-speed shafts 5 and H. A similarcircular gear 2i is shown in Figs. 19and 20, held stationary in the closed container formed by thecorresponding half-shells I9 and 29 by .bolts 22. These circular gears 3and 2| are shown respectively replaced in the modification of Figs. 21to 24, by an un- =toothed friction-gear annulus I53, held stationary inthe closed container formed by the halfshells I5I and I52 by bolts I54and a frictiondisc gear I13 in contact therewith. The correspondingannulus I2 of Figs. 25 and 26 is held stationary in the closed containerformed by the half-shells I0 and II by bolts I3. The half-shells 94 and95 are held together as a closed container by bolts 96.

The embodiment of the invention that is illustrated in Figs. 1 to 18 and31 comprises a twopart arm, shown intermediately fixed between its twoparts I and 8 to the high-speed shaft 5, so as to rotate therewith. Agear member H9 is freely pivoted on a pintle Ill carried by the part Iof this two-part arm, to one side of the highspeed shaft 5. The gearmember H9, therefore, rotates with the high-speed shaft 5, in a circularorbit about the axis of the alined high-speed and low-speed shafts 5 andIT, as shown in Figs. 6 to 11. Ball bearings, with a loaded thrust, maybe interposed between the gear member H9 and the pintle I0, but they areomitted from the drawings, in order to simplify the disclosure. Theother part 8 of the two-part arm carries a counterweight I I, held inplace by a screw l2.

Since the teeth of the gear H9 are arranged externally, it will beconvenient to distinguish between the two gears by referring to the gear3 as an internal gear and the gear H9 as an external gear.

The teeth of the external gear H9 mesh with the teeth of the internalgear 3. During the rotation of the high-speed shaft 5, therefore, y g hee terna gear I I 9 in its circular orbit about the high-speed shaft 5,the external gear H9, by reason of this meshing engagement of the gears3 and I I9, will rotate about its pintle Ill.

The anti-clockwise-indicating arrows 225 of Figs. 6 to 11 indicate thedirection of rotation of the high-speed shaft 5 and, therefore, thedirection of travel of the external gear H9 in its circular orbit. Theclockwise-indicating arrows 226 of Figs. 6 to 11 indicate the directionof rotation of the external gear H9 during its travel in its circularorbit.

These directions of rotation, indicated by the arrows 225 and 226 ofFigs. 6 to 11, are the same as those shown in Fig. 14, where the largedotand-dash circle, marked 3 or I2, of radius R, represents thestationary internal gear 3, and the small circle, marked H9 or 83, ofradius 1, represents the external gear I I9. The common axis of thealined high-speed and low-speed shafts 5 and I1 is represented in Fig.14 at 0.

Let it be assumed, as shown by the dot-anddash lines at the extremeright of Fig. 14, that the gears 3 and H9 were initially in tangentialcontact, with a point A of the periphery of the external gear H9coincident with a point B of the periphery of the internal gear 3. Thecenter G of the external gear H9, corresponding to the pintle I9, andthe point P, representing a pintle projection I23 that is immovablyfixed to the external gear H9, so as to be rotatable therewith,

will therefore be disposed initially along the diameter B of theinternal gear 3, as shown.

Let it be assumed further that the high-speed shaft has been rotatedanti-clockwise through an angle 6 in the direction of the arrow 225 ofFigs. 14 and 15. The gear I I9 will therefore have been carried by thehigh-speed shaft 5, in its circular orbit 221 of Fig. 15,anti-clockwise, through the angle 0. During its resulting rotation aboutits pintle I9, represented at G, it will therefore have rolled along theinternal gear 3 clockwise, in the direction of the arrow 225 from itsabovereferred-to initial position into the further position shown inFig. 14, through an angle 4:. The center G has accordingly traveledalong the dotand-dash circular arc, represented by 227 in Fig. 15,coincident with the circular orbit of travel of the external gear I I9about the common axis 0 of the alined high-speed and low-speed shafts 5and IT.

For illustrative purposes, the radius R of the internal gear 3 is shownapproximately double that of the radius 'r of the external gear I I9.According to the embodiment of the invention illustrated by Figs. 1 to18 and 31, it is shown a little smaller than twice the radius r of theexternal gear H9. A similar relation holds between the radius R of theuntoothed friction-gear annulus I53 of the embodiment of the inventionillustrated by Figs. 21 to 24 and the radius 1' of the friction-discgear I13 in contact therewith. The radius R of the internal gear 2| ofFigs. 19 and is shown a little larger than twice the radius 1 of thecorresponding external gear 27.

Though the practice of the invention is not dependent upon the choice ofthis particular approximate ratio 2 to 1, such choice will help towardan explanation of the principles underlying the invention.

To facilitate the explanation, it will be assumed, for the moment, thatthis ratio had been chosen exactly 2 to 1. Then, by the time that theexternal gear H9 would have become rotated throughout a completerevolution about its pivoting pintle I9, corresponding to which 4 wouldhave been equal to 360 degrees, the high-speed shaft 5 would have becomerotated through a half-revolution, making 0 equal to degrees. Thbefore-mentioned point A on the periphery of the small gear I I9 thatwas initially coincident with the point B on the periphery of theinternal gear 3, therefore, would then have reached the point C,diametrically opposite to the point B on the periphery of the internalgear 3.

As already stated, however, the radius r of the external gear I I 9 isshown, in the modification of Figs. 1 to 18 and 31, as somewhat largerthan half the radius R of the internal gear 3. By the time that theexternal gear H9 has become rotated throughout a complete revolutionabout its pivoting pintle I9, therefore, making equal to 360, the pointA on the periphery of the external gear H9 has reached a point D of theinternal gear 3 that is beyond the point C. This is the situationrepresented in Fig. 15, where the pintle I0 has now assumed the positionG1. The external gear I I9 has therefore rolled along the internal gear3 through an arc of the internal gear such that 0 is greater than 180degrees. The excess arc CD will obviously be 21r71rR.

By the time that the external gear H9 has rolled further along theinternal gear 3, so as to complete two revolutions about its pintle I0,corresponding to 5 equal to 720 degrees, therefore, it will have assumeda new position such that the point A will have reached a point E, Fig.16, where the arc BE is twice as great as the arc CD. The point A hastherefore advanced anti-clockwise along the periphery of the internalgear 3, from its initial position, coincident with B, to the point E,and the pintle II) has now assumed the position G2 of Fig. 16. The angle0 through which the high-speed shaft 5 has now rotated is 360 degreesplus an additional angle represented by the arc BE of Fig. 16.

Further rotation of the high-speed shaft 5, as will be more fullyexplained presently, will cause the point A on the periphery of theexternal gear H9 to advance farther and farther anti-clockwise along theperiphery of the internal gear 3, as shown at F in Fig. 1'7 and H inFig. 18.

It has been stated that the pintle projection I23 is immovably fixed tothe external gear H9, so as to be rotatable therewith, and that it isrepresented by the point P. This point P is shown at a distance S fromthe point A. During the rolling movement of the external gear H9 alongthe internal gear 9, therefore, the pintle I23, represented by the pointP, travels along a hypotrochoidal path. Four successively disposedbranches of this hypotrochoidal path are respectively represented inFigs. 15 to 18, inclusive, at PP1, P1P2, P2P3, and P3P4.

Had the pintle projection I23 been positioned along the periphery of theexternal gear H9, as at the point A, its path of travel would have beenhypocycloidal, instead of hypotrochoidal; and if the radius r of theexternal gear H9 had been exactly half of the radius R of the internalgear 3, the hypocycloid would have degenerated into a straight linecoinciding with the diameter BC of the internal gear 3.

An approximation to this straight-line path of travel of the pintleprojection I23 along a diameter of the external gear 3 through thecenter 0 of this internal gear 3 may be obtained by employing thebefore-discussed approximate 2 to 1 ratio of R to r and properlychoosing the distance S. The full-line hypotrochoidal branches PP1,PlPz, PzPs and P31 4 of Figs. 15

to 18 areapproximately straight, they are dis-- posed nearly incoincidence with diameters of the internal gear 3, and they all passthrough the center of the internal gear 3. They are nevertheless'sufficiently curved, and always in the same direction, to cause thepintle projection I23 to rotate progressively anti-clockwise during thecontinued rotation of the high-speed shaft and the consequent rollingmovement of the external gear H9 along the internal gear 3.

During one complete revolution of the external gear H9, thehypotrochoidal branch PPI of Fig. 15 is described, starting out from itsinitial position P on the diameter BC of the internal gear 3 and endingat P, at the free end of the radius OGlPlD- During this time, thehigh-speed shaft 5, carrying with it the external gear I I9, rotatesanti-clockwise, in the direction indicated by the arrow 225, through the180 degree angle 0 corresponding to the upper semi-circle BC of Fig.15plus an angle corresponding to the arc CD, the pintle I0 at the centerof the external gear H9 travels anti-clockwise, along the dot-and dashcircular orbit 221 of Fig. 15, concentric with the point 0, from theposition G to the position G1, and the pintle I23 travels along thishypotrochoidal branch PP1, from its initial position P, to its endposition P1.

The point P1 represents also the beginning of the next hypotrochoidalbranch, as shown in Fig. 16. During the further travel of the externalgear H9 in its circular orbit, along the dot-anddash'path 228 of Fig.16, the pintle II], at its center, travels, in the same anti-clockwisedirection,,indicated by the arrow 229, from the point G1 to the pointG2. The projecting pintle I23 has therefore traveled further, this timealong this next'hypotrochoidal branch, from its beginning point P1 toits end point P2. The external gear H9 has now completed tworevolutions, corresponding to which the angle equals 720 degrees.

If the ratio of R to r had been exactly 2 to 1,

the point A of the external gear H9 would now have become restored toits original initial position, coincident with the point B of theinternal gear 3. Because the ratio of R to r is a little more than 2 to1, however, the point A of the external gear H9, at the end of two ofits revolutions, as already explained, will have reached the point E, asdiagrammatically shown in Fig. 16, at the free end of the radius OG2P2E.

With further continued rotation of the highspeed shaft 5, and withcorresponding continued rolling of the external gear I I9 along theinternal gear 3, the operation thus far described will be repeated;bearing 'in mind, however, that the initial position of the gears 3 and'I I9 will now be regarded as indicated in Fig. 16, with the point Aofthe external gear I I9 assumed to be in coincidence with the point E,instead of with the point B of Fig. 14.. The end 'point P2 of thehypotrochoidal branch P1P2 will now be the beginning of thehypotrochoidal branch following, the end point of which is shown in Fig.17 at P3. The pintle I23 will travel along this hypotrochoidal branchP2P3 during the travel of the pintle ID at the center of the externalgear H9 from the'point G2 to the pointGa, along the portion 230 of itscircular arc of travel, in the direction of the arrow 23I. Fig. 17,therefore, is pre-- cisely the same as Fig. 15, except that it has beenarrived at by considering the initial position of the parts as shown inFig. 16, whereas Fig. 15 was obtained by considering the initialposition of the parts as shown in Fig. 14. Fig. 17 may therefore beobtained by rotating Fig. 15, in the-direction of the anti-clockwiseindicating arrow 229, through an angle corresponding to the arc BE ofFig. 16. The are CF of Fig. 18 is equal to the sum of the arcs CD ofFig. 15 and BE of Fig. 16.

As the pintle III, at the center of the external gear I I9, travelsfurther along the portion 2320f its dot-and-dash-line orbit in thedirection 233, from the point Gs of Fig. 1'7, to the point G4 of Fig.18, the hypotrochoidal branch shown in Fig. 18 becomes traced out by thepintle I23, from its beginning point P3 to its end point P4.

This progressive anti-clockwise rotation of this nearly-straight-linehypotrochoidal path of travel of the pintle I23 is utilized, accordingto the embodiment of the present invention that is illustrated in Figs.1 to 18 and 31, to reduce the high-speed travel of the high-speed shaft5 to the low-speed travel of the low-speed shaft I'I. According to thisembodiment of the invention, therefore, the high-speed shaft 5 may beregarded as the control shaft, and the low-speed shaft IT as thecontrolled shaft.

To the attainment of this end, the pintle projection I23, or, rather, awedge I28 that is freely pivoted about the pintle I23, so as to projectfrom the gear member I I9 into a straight-line slot I21 of a disc memberI25 is fixed to the low-speed shaft I'I, so as to rotate therewith. Thestraight line slot I2! is V-shaped, in transverse cross-section, tocorrespond to the transverse cross-section of the wedge I28. The wedgeprojection I28 is therefore slidably mounted between the walls of theguide slot I21. The guide slot I2! is symmetrically disposed withrespect to the common axis of the alined high-speed and lowspeed shaftsin order that its center may be disposed on that common axis. The pintleprojection I23 and the wedge projection I28 mounted thereon, therefore,oscillate back and forth in the guide slot I21 along the hypotrochoidalpath before described, passing through the center of the guide slot I21each time that it oscillates from one end of the guide slot I21 to theother end. The high-speed control shaft 5 thus maintains control overthe controlled low-speed shaft I! through the engagement of the controlprojezclting wedge I28 with the walls of the guide slot The two-part armI, 8 has been described as rotated by the high-speed shaft 5. The discI26 is similarly rotated with the low-speed shaft I1, and about the samealined axis of the high-speed and low-speed shafts 5 and I1, representedat O in Figs. 14 to 18. The straight-line slot I21 intersects thiscommon axis and is symmetrically disposed with respect thereto.

The relation of the parts may, of course, be reversed. The slot I21 maybe provided on a member carried by the pintle I 23, and the wedge I23may be carried by the low-speed shaft H.

In Fig. 6, as in Figs. 1 and 2, the wedge I23 which, as before stated,is freely mounted pivotally about the pintle I23, is shown centered onthe axis of the alined high-speed and low-speed shafts 5 and I1. Duringthe travel of the gear H9 from the position of Fig. 6 to that of Fig.'7, therefore, the projecting Wedge I28 on the pintle projection I23will travel along the first approximately straight hypotrochoidal branchPPl away from this axis, to the position indicated by dotted lines inFig. 7. The resulting engagement of the wedge I28 with the walls of theslot I21 into which it projects will cause the disc I26 to travelthrough an angle anti-clockwise, in the direction of the arrow 225, fromthe position of Figs. 1, 2 and 6, to that of Fig. 7 with consequentanti-clockwise rotation of the low-speed shaft I1 to which it issecured. The anti-clockwise rotation may be observed by inspection,through noting that the dotted-line showing of the slot I21 is displacedin Fig. 7 anti-clockwise compared to the showing of Fig. 6.

The comparatively large angle through which the external gear H9 hasbeen carried anticlockwise in its circular orbit, from the positionshown in Fig. 6 to that of Fig. 7, representing the correspondinganti-clockwise rotation of the high-speed shaft 5, has therefore beenconverted into a comparatively small angle of anti-clockwise rotation ofthe low-speed shaft I1, represented by the relatively small angle ofdisplacement of the disc I26 from the position of Figs. 1, 2 and 6, intothat of Fig. 7. This angle of anticlockwise rotation of the low-speedshaft I1 is represented at w in Fig. 14.

Further continued anti-clockwise rotation of the high-speed shaft 5 willcarry the external gear H9 from the position of Fig. 7 to that of Fig.8. By the time that the high-speed shaft 5 has rotated through 180degrees anti-clockwise, in the direction of the arrow 225 of Fig. 15,the parts will occupy the positions illustrated in Fig. 9. During this180 degree rotation of highspeed shaft 5, the wedge I28, on the pintleI23, will have travelled further along the slot I21, along the samehypotrochoidal branch PP1, from the position of Fig. 8 to that of Fig, 3or Fig. 9.

An anti-clockwise rotation of the high-speed shaft 5 through an angle 0equal to 180 degrees, carrying the external gear H9 in its orbit alsothrough 180 degrees, from the position of Figs. 1, 2 and 6 to that ofFig. 9, has therefore now been converted into a relatively smallanti-clockwise rotation of the low-speed shaft I1, represented by theangular difference a between the positions occupied by the disc I26 inFigs. 6 and 9.

Rotation of the high-speed shaft 5 through a further angle, representedby the arc CD of Fig. 14, will result in the wedge I28 reaching the endlimit of its outward travel along the said hypotrochoidal branch PP1 inthe slot I21, as representel in Fig. 15, which limit constitutes alsothe beginning limit P1 of the next branch PlPZ of the hypotrochoidalpath. as illustrated in Fig. 16. The parts will then occupy a positionbetween the positions of Figs. 9 and 10. The angular travel 1:: of thedisc I26 and, therefore, of the low-speed shaft I1 to which it issecured, of course, will have become correspondingly increased.

With further continued anti-clockwise rotation of the high-speed shaft5, carrying the external gear I I9 with it, the wedge I28 retraces itstravel in the slot I21, as a comparison of the positions of the wedgeI28 in Figs. 9 and 11 will demonstrate. This retraced travel, however,is along the next branch P1Pz of the hypotrochoidal curve, asillustrated by Fig. 16. The angular travel w of the disc I26, however,is nevertheless continued in the same anti-clockwise direction,represented by the arrow 229 of Fig. 16, which is the same as that ofthe arrow 225 of Fig. 11.

As the high-speed shaft 5 continues to rotate anti-clockwise, carryingthe external gear I I9 beyond the position of Fig. 11', the wedge I26 onthe pintle I23 continues its retracing movement in the slot' I21alongthe saidnext branch 10 P1P'2 of the hypotrochoidal path. Afterreturning to its central position, the wedge I28 will travel therebeyonduntil it reaches the opposite extreme position, represented by the pointP2 of Fig. 16.

By the time that the high-speed shaft 5has been rotated throughout onecomplete revolution, as before explained, the external gear H9 will havebeen carried in its circular orbit back to and beyond the originalposition, illustrated in Fig. 6. The low-speed shaft I1, however, willhave completed only a very small fraction of a revolution, representedby the angular diiference w between the position of the disc I26 shownin Fig. 6 and the position of the same disc I26 occupying a positionsomewhat in advance of that illustrated in Fig. 11.

With still further continued clockwise rotation of the high-speed shaft5, carrying the external gear H9 with it, the wedge I28 will continueits travel in the slot I21 to the end limit P3 of the said next branchP2P3 of the hypotrochoidal path, as represented in Fig. '17.

According to a feature of the present invention, therefore, tworelatively movable members H9 and I26 are provided, of which the memberI I9 may be an external circular gear member that is movable relativelyto the internal circular gear member 3. The member H9 may be referred toas a control member, because it is fixed to travel with the high-speedcontrol shaft 5. The controlled member I26 is fixed to the lowspeedcontrolled shaft. The control member I I9 is provided with theprojecting pintle I23 upon which the wedge projection I28 is mounted.The pintle I23 and the wedge'I28 may be referred to as controlprojections, because they are part of the external gear H9, that ismounted upon the high-speed control shaft 5. Though the pintle I23 isfixed to the member H9, so as to be immovable relatively thereto, it isalso slidable in the slot I21 of the member I26 and the controlledlow-speed shaft I1 to which it is fixed in response to the rollingmovement of the gear member H9 along the internal gear member 3. Thegear member H9 is so connected to the highspeed shaft 5 as to berotatable therewith in a circular orbit 221, 228, 230, 232 about theaxis of this shaft 5. As the disc member I26 is fixed to the low-speedshaft I1, and as the low-speed shaft I1 is alined with the high-speedshaft 5, the member I26 is pivotally movable about the common axis ofthe alined high-speed and lowspeed shafts 5 and I1. Rotation is thustransmitted at reduced speed from the high-speed shaft 5 to thelow-speed shaft I1.

The degree of speed reduction between the high-speed and low-speedshafts 5 and I 1, as will presently appear, is a simple function of theradius R of the internal gear 3 and the radius 1 of the external gearH9. .The direction of ro tation of the disc I26 and, therefore, of thelowspeed shaft I1, shown anti-clockwise, as will also presently appear,is also determined by the relative values of the radii R and 1.

That the direction of this rotation of the disc I 26 is correctly shownthe same as that of the high-speed shaft 5 is evident from thediscussion above of Figs. 14 to 13; for, at the end of two completerevolutions of the external gear I I9, the peripheral point A, occupyinginitially the point B, assumes the position E, beyond the initial pointB of the internal gear 3. This results from the fact, as beforeexplained, that the radius r of the external gear H9 is larger than halfthe rag a ll radius R of the internal gear 3. The point P of theexternal gear II9, initially occupying a position just to the left ofthe point B, as shown in Figs. 14 and 15, therefore, similarly nowoccupies the position P2 of Fig. 16. As the point P represents thepintle projection I23, the disc I26, in the slot I21 of which the wedgeI28 is positioned, becomes thus farther advanced angularly along thecircular arc 228 during the continued rotation of the high-speed shaft5. The disc I26 was originally positioned with the point P along thediameter BC of the internal gear 3. The wedge I28, however, has nowcarried this disc I26 through an angle such that it occupies theposition P2 of Fig. 16, and in a direction the same as the direction ofrotation of the high-speed shaft 5. As the disc I26 is fixed to thelow-speed shaft I1, the low-speed shaft I1 has been rotated through thesame angle, in the same direction.

If the radius r of the external gear II9 were smaller than half theradius R of the internal gear 3, however, as will be explainedhereinafter, a rotation of the high-speed shaft 5 in one direction wouldbe converted into a rotation of the low-speed shaft I1, in the oppositedirection.

It is now in order to explain the mathematical theory underlying theoperation of the embodiment of the invention that is disclosed in Figs.1 to 18, inclusive, and 31.

To summarize, it has been assumed that the large circle of Fig. 14represents the stationary internal gear 3, of radius R, and the smallcircle the rolling external gear I I9, of radius T. It has been assumedalso thatthe two gears 3 and H9 were originally disposed so that theperipheral point A of the external gear H9 was coincident withtheperipheral point B of the internal gear 3; and that, in response tothe anti-clockwise rotationof the, high-speed shaft 5 through the angle0, the external gear H9 has rolled along the internal gear 3 through theangle 5. During this rolling movement, the pintle I23 represented by thepoint P, at a distance S from the peripheral pointA of the external gearH9, has engaged the walls .of the slot I21 to effect rotation of thedisc I26 that is provided with the slot I21.

It has further been assumed that, during the time that the high-speedshaft 5 has rotated through the angle 0, and the external gear H9,therefore, has rolled through the angle the disc I26, provided with theslot I21, has rotated through an anglew, to assume the position OP ofFig. 14. As the disc I26 is integral with the low-speed shaft I1,therefore, the low-speed shaft I1 has likewise rotated through the angleto. The rotation of the high-speed shaft 5 through the angle hasaccordingly become converted into rotation of the low-speed shaft I1through the smaller angle :0, and in the same anti-clockwise direction.v

It is proposed to find the value of the angle 0: of rotation of thelow-speed shaft I1 in terms of the angle 0 of rotation of the high-speedshaft and the respective radii R and 1' of the internal r:(R-r) cos 0+(r-s) cos 5-0) yi(Rr) sin 0(i.'-'-'s) sin (''0) As, moreover, the arerolled out along the. external gear H9 is of the same length as the arerolled out on the internal gear 3-,

Rdzflfi I Since the pintle I25 represented at P,- furthermore, must passthrough the center O,

R7:TS' The equations of the hypotrochoid therefore reduce to whence Itfollows that 2r-R 21' 2/ There is also a further solution, involving thesame angle augmented by i The first of these solutions applies to thepart of each hypotrochoidal branch on one side of the center 0, and theother to the part of th'e'same hypotrochoidal branch on the'other sideof that center. Since the same (list: I26 is involved in both cases,however, there is really only one and the same solution, insofar as therelation between the speed of rotation of the mar-speed Shaft IT withrespect to that of the high-speed 5 is cofl cerned.

The solution may be obtained also geemetr-ically, merely bynoting, inFigs. 14 and 31, that the triangle GOP is isosceles; The angesoppositethe equal sides GO and GP of this triangle, there'- fore, are each equalto it follows, from mere inspection, that 2rjR 2R S This geometricsolution, however, is obtained for the first quadrant only, and onlyforthe particular relative values of Rand r shown in Figs. 14 and 31. Theanalytic solution above, on the other hand, is perfectly general.

The low-speed shaft I-1 thils rotates at a speed that is the same asthat of the high-speed shaft 5, multiplied by a constantfra'ction ofwhich the numerator is the radial distance Shoffth'e. pintle I23 fromthe periphery of the 'ex'ternalge'ar. I I9, andthe denominatoris thediametergr of the external gear I I 9. This fraction is less than um tyby a fraction equal to the ratio of the radius R of the large fixedinternal gear 3 to the diameter of the small rolling external gear H9.If the high-speed shaft rotates uniformly, therefore, it will rotate thelow-speed shaft I1 uniformly, at this reduced rate.

In Figs. 15 to 18, it is assumed that the ratio At each completerevolution of the external gear H9, therefore, the external gear II9rolls over a portion of the periphery of the internal gear 3 equal to180 degrees plus an arc CD equal to 22%.; degrees. At the end of fourrevolutions of the external gear I I9, accordingly, the pintle I23,represented by the point P, will have become rotated through an angle of90 degrees, as may be observed by comparing the position of P in Fig. 15with that of P4 in Fig. 18. The high-speed shaft 5, therefore, will havebecome rotated through two complete revolutions plus 90 degrees duringthe time that the low-speed shaft I1 will have become rotated throughonly 90 degrees.

It is found, in practice, that if only one control wedge member I28 isemployed, it often loses control slightly at times when, during itsoscillatory movements, it passes through the center of the guide slotI21, alined with the common axis of the high-speed and low-speed shafts5 and I1. Though it automatically corrects for the slight misorientationof the controlled disc member I26 thus produced as soon as it passesthis dead-center position, such automatic reorientation is frequentlyattended by loud noises resulting from the control wedge projection I28hammering against the walls of the guide slot I21 during the process ofthis reorientation. At times, furthermore, the control wedge projectionI 28 stops altogether in its said position of dead center, without anyfurther travel back and forth in the guide slot I21. The high-speedcontrol shaft 5 then continues rotating, but without any further controlover the low-speed shaft I1. In order to reestablish the control of thehigh-speed shaft 5 through the control wedge projection I28, it thenbecomes necessary first to reorient the controlled disc member I25 toits proper angular position, after which it becomes possible to actuatethe control wedge projection I28 out of its dead-center position, andinto another portion of the guide slot I21, so as to enable it toreassume control over the controlled disc member I26.

. In accordance with a feature of the present invention, however, thehigh-speed control shaft 5 is provided with more than one control wedgeprojection I28, and the number of guide slots I21 is correspondinglyincreased, so as to provide a separate guide slot for each wedgeprojection I 28. According to the specific embodiment of the inventionthat is herein illustrated and described, the high-speed control shaft 5is provided with two diametrically opposed control wedge projectionsI28, respectively slidable in two guide slots I21 provided upon thecontrol disc member I20 at right angles to each other. This is moreparticularly illustrated in Figs. 12 and 13.

At times when one of the control wedge projections I23, during thetravel of the control gear member H9 in its circular orbit 221, 228,230, 232 about the common axis 0 of the alined shafts, happens to bepassing through its deadcenter position, the other control projectionI28 will therefore be occupying a position at one of the ends of itsguide slot. To compensate for the possible loss of control of thecontrolled disc member I26 by the said one control wedge projection I28at the dead-center position, therefore, the other projection I28 willexert a maximum. leverage upon the controlled disc member I26. When thisother wedge projection I 26, in turn, occupies its dead-center position,on the other hand, the said one wedge projection I28 will exert themaximum leverage. The controlled disc member I20 and the low-speed shaftI1 to which it is fixed will thus be under full control at all times tomaintain the rotation of the low-speed shaft steady.

As an alternative construction for effecting the same result, anadditional external gear II9 might be provided diametrically opposite tothe external gear I I9 shown, and rotatable therewith from thehigh-speed shaft 5. These two gears would be provided, each with one ofthe wedges I28, and each riding in one of the wedge-shaped slots I21 ofthe disc I26.

The two wedge projections I28 are illustrated in Figs. 1, 2 and 3 asmounted upon two respective pintles I23 that are carried at oppositeends of an arm I20. The arm I20 is held to the external gear member II9by means of screws I2I, and guide pins I22 are provided to help preventrotation thereof With respect to the external gear member H9. It is, ofcourse, obvious, that the members I28 need not be in the form of wedges.The wedge construction, however, helps to prevent lost motion withrespect to the walls of the \/-shaped slots I21. In order the better toeffectuate his result, the ends of a leaf spring I24, intermediatelyheld to the arm I20 by a screw I25, are interposed around the pintleprojections between the wedges I28 and the arm I20. The wedge shapepermits also of taking up wear between the faces of the wedges and thewalls of the guide slots in which they slide. The angle of the wedge ispreferably 60 degrees. The wedges may be provided with ball bearings,not shown. The projections about which the wedges are pivoted may rotatein holes in the arms I20 provided with the ball bearings. In order toreduce the efiects produced by the inertia of a large disc member I26,it is shown provided with perforations I29.

The invention is, however, operative with only a single wedge projectionI28. For this reason, and also in order to simplify the disclosure, thesingle-wedge-projection modification is illustrated in Figs. 6 to 11,with the disc I26 shown broken away.

If the radius r of the external gear I Hi had been less than half theradius R of the internal gear 3, it would have been necessar to mountthe pintle I23 upon an arm extending rigidly beyond the periphery of thegear H9. A construction of this kind is illustrated in Figs. 19 and 20,the radius r of the external gear 21 of which, as before stated, issomewhat less than half the radius R of the internal gear 2 I.

The diagram for this case corresponding to Fig. 14 appears in Fig. 29.The internal gear 2I is represented by the large dot-and-dash circle ofFig. 29, marked 2| or I53, and the external gear 21 by the smalldot-and-dash circle, marked 21 or I59. The line- OP is marked I35 orISI.

To the two-part arm 1, 8 of Figs. 1 to 11 corresponds the two-part arm25, 26 of Figs. 19 and 20. The part 25 of the two-part arm 25, 26carries the counterweight 31, corresponding to the counterweight I I,held in place by a screw 38.

The part 25 carries a pintle 28, corresponding to the pintle it, aboutwhich the external gear 21 is pivoted. The pintles I33 correspond to thepintles I23. About these pintles I23 are pivoted wedges I38,corresponding to the wedges I28, which engage the walls of guide slotsI31 of a disc I36, perforated at I39, corresponding to the guide slots121 of the perforated disc I26.

In order that the hypotrochoidal path of travel of each pintle I33 maypass through the center of the internal gear 24, the same as thehypotrochoidal path of travel of each corresponding pintle I23 passesthrough the center of the internal gear 3, as shown in Figs. 14 to 18,it becomes necessary, as already stated, to mount :it external to theperiphery of the gear 21. According to the embodiment of the inventionthat is illustrated in Figs. 19 and 20, this is effected by mounting thepintles I33 upon an arm I30 that may be fixed to the gear 21 by screwsI3I, but relatively farther out than the pintles I23 are mounted on thecorresponding arm I20. The sprin I34 is held to the arm I30 by a screwI35, and performs the same function as the spring IZ I.

It has been explained that, since the radius r of the external-gear H9is greater than half the radius R of the internal gear 3 of Figs. 1 to18 and 31, the externalgear I I9, during a complete revolution, rollsalong an arc of the internal gear '3 somewhat greater than 180 degrees,the excess being represented by the arc CD of Fig. 14. Since the radius1' of the external gear 21 is less than half the radius R of theinternal gear 2I, on the other hand, the gear 21, during a completerevolution thereof, rolls along an arc of the internal gear 2I somewhatless than 180 degrees. The deficiency of the arc is TR-2T7, representedin Fig. 29 by the arc IC.

It has also been explained that, because of the excess arc CD of Fig.14, the disc I26, with its slot I21, is rotated, together with thelow-speed shaft I1 to which itis attached, as shown in Figs. 6 to 11, inthe same direction as the high-speed shaft .5. In the modification ofFigs. 19 and.20,"on the other hand, because the gea 21, during acomplete revolution, rolls along an arc of the internal gear 2I somewhatless than 180 degrees, the disc I36, with its slot I31, corresponding tothe disc I26, with its slot I21, is rotated in a direction opposite tothe direction of rotation .of .the two-part arm 25, 26. Rotation of thetwo-part arm .25, 2.6 in one direction, therefore, willeffect rotationof the low-speed shaft 35 in the opposite direction. This is readilyapparent geometrically from Fig..29, since the arc BI is less than thesemicircular arc BC, and it may also be demonstrated analytically.

It is possible to derive the-equations for the hypotrochoidal path oftravel of the pintle I33 byinspection of Fig. 29. The analytic solutionderived above, however, may be applied to this case also, if it is bornein mind that the sign of S is now negative. The ratio of the speedreductionbetween the two-part arm25, .26 and the lowspeed shaft 35 may.be represented by the same formulas alreadyderived, but with anegativesign, since the angle is negativa'These formulas may also be obtainedgeometrically from an inspection of Fig. 29, bearing in mind that thetriangle GOP is isosceles.

24-, to which the two-part arm 25, 2B is secured.

and thelow-speed shaft 35. To obtain the speed reduction between thehigh-speed shaft .40 and the low-speed shaft 35, it is necessary tomultiply this ratio by the'ratio between the radius of a gear 39, thatis integral with the high-speed shaft 40, and the radius of the externalgear 21, in meshing engagement therewith. A further speed reduction isthus obtained by causing the external gear 21 to mesh with both theinternal gear 2I and the gear 3,3that is fixed to the highspeed shaft40.

This further speed reduction is not, of course, limited to theparticular modification .of Figs. 19 and 20.

A further speed reduction still, moreover, could be obtained byinterposing additional gears. The relative directions of rotation ofthehighspeed and the low-speedshafts 40 .and '35 could also be changedthrough the medium .of this ex pedient.

The sleeve 24 is disposed loosely between the highspeed shaft 45 .andthe journal bearing 23. As in the embodiment of the inventionillustrated by Figs. 1 to 18 and 31, the partsare shown held securely inplaceon the highspeed shaft II) by the thrust collar 42 that .is securedto the high-speed shaft All by the pin43 extending through thecok lar 42and the shaft 40, with a Washer or ball: bearing .4] is interposed.Thesleeye 5.6 is similarly held in place.

In respects otherthan the reversal of the dimertion of rotation of thelow-speed shaft 35, with correspondingto modification of theshape of thehypotrochoidal-branch paths shown in Figs. 1 5 to 18, to provideepitroch-oids, instead, andinrespects other than is involved in theintroduction of the inter-mediate gear 39, the operation of themodification shown in'Figs. 19 and 20 is substantially the same asdescribed in connection with Figs. 1 to '18 and 31.

It is not essential that the rolling relation ;between the externallycontoured member I I9 or 21 and the corresponding internally contouredmember '3 or 21 be effected by mean Of gear teeth. .A similar result maybe obtained iii-other ways as, for example, frictionally. The replacement of the rolling-gear action by frictional rolling is illustrated inmodification of Figs. ,21 .to 24 and also the modification of Figs.2,5.and;2,6i.

Theparts -1-a-nd- 8 ofthe two-,part armofFigs. 1 to 18 and 31 arerepresented in Figs. 21 to 24 at I51 and I58,-respectively. The partI58=carries a counterweight-I 6 I ecured by ascrew 1162." The part 151is provided with-a pintle-1,65 about which is pivoted the circularlycontoured friction gear ,wheel I59, corresponding to the external gearM9 or 21, and the external periphery of which carries a replaceable tireI13 that engages frictionally, in rolling contact, with the inner.peripheral contour of the "annulus -.I,53,,correspondingtotheinternalgear3 or-ZI.

The-radius r of the tire :I13 is shown slightly smaller, than half theradius R of the annulus 153, corresponding tothe showing-of Figs. 19 and20,, wherethe radius r of the externalgear 21 is shown slightlysmallerthan half the radius R of the internal gear 21. The diagram of Fig. ,29,therefore, is asapplicable to this embodimentof the invention asto theembodiment shown inFigs. 19 and 20. The large dot- -and-dash circlemayrepresent the stationary annulus I53 and the small the tire I13.

The pintles 119 of this embodiment ofthe invention, corresponding to thepin I33 of Figs. 19 'and'20, are therefore shown carried upon an arm114, similar to the arm woof Figs. 19 and20, hem

fixed to the wheel I59 by screws I15. The spring I11, held to the armI14 by a screw I18, corresponds to the springs I24 and I34, and theguide pins I16 to the guide pins 22. The pintles I19 are confined totravel, in their respective hypotrochoidal paths, back and forth throughthe center 0, Fig. 29, of the annulus I53, the same as the pintles I23must travel through the center of the internal gear 3 and the pintlesI33 through the center 0 of the internal gear 2I. Wedges I80, freelypivoted on the respective pintles I19, corresponding to the wedges I28and I38, ride in respective guide slots I82 of a disc I8I, perforated at205, corresponding to the perforated slotted discs I26 and I35. The discI8I is secured to the low-speed shaft I83, so as to rotate there with.

The high-speed shaft I55 is shown mounted in a journal bearing I56. Theparts are shown held securely in place on the high-speed shaft I55 by athrust collar I64 that is secured to the high-speed shaft I55 by a screwI65 extending through the collar I64, with a ball bearing I63interposed. The low-speed shaft I83 is similarly mounted in a journalbearing 68. A thrust collar I86, corresponding to the thrust collar I64,is held in place by a screw I81, with a ball bearing I 85 interposed.

As the tire I13 wears away, and as the inner wall of the annulus I53 mayalso wear away, it may become necessary, from time to time, in orderthat the pintles I19 may always pass through the center 0 of the annulusI53, to re adjust the position of the wheel I59. Such readjustment maybe accomplished in any desired way, as by mounting the screw I15 inelongated slots, not shown, of the arm I14. The illustrated adjustmentinvolves mounting the pintle I60, about which the wheel I59 is freelypivoted, on an eccentric I69 that may be rotatably adjusted by means ofa suitable tool inserted into openings I18. The parts may be tightenedin eccentrically adjusted position by means of a screw or bolt 204 forclamping together separated arms of the part or element I51 betweenwhich the eccentric I59 is received. In this manner, it is possible tomaintain always the proper degree of pressure of the tire I13 againstthe inner wall of the annulus I53. As the tire I13 or the inner wall ofthe annulus I53 wears down, all that is necessary is to readjust thispressure, by means of the eccentric I69. Such readjustment, even withoutwearing down, could be utilized also, within limits, to control somewhatthe degree of speed reduction.

The counterweight I6I may be adjusted to correspond to the adjustment ofthe wheel I59. It is mounted upon a bolt I62 that is eccentricallymounted between the separated arms of the element I58 by means of aneccentric I61 similar to the eccentric I69. The opening I68 of theeccentric I61 serve a function similar to that of the openings I18 ofthe eccentric I69, and a bolt 203 corresponds to the bolt 284.

The tire I13 is held in place on the periphery of the wheel I59 in aperipheral recess that'is L-shaped in cross section, as shown in Fig.24, between the short leg of the L and a metal disc 201 that is securedto the wheel I59 by screws 288. Ball bearings I H are interposed betweenthe disc 281 and the eccentric I69. Ball bearings I12 are similarlyinterposed between the other face of the wheel I59 and a nut that isthreaded on the free end of the pintle I60.

One of the objects of the present invention has been stated above toreside in varying the speed 18 reduction or increase. According to thespecific embodiment of the invention that is herein illustrated anddescribed, this result is attained by adjusting the length of theperiphery of the annular gear I53. To this end, the annulus I53 is shownsplit. A wide range of speed ratios may therefore be attained, duringthe operation of the/machine, merely by increasing or decreasing thecircumference of the annulus I59. The range of adjustment may be such,indeed, as to render it possible: first, to stop altogether the rotationof the controlled shaft, whether low-speed or highspeed; and then bycontinuing the adjustment in the same direction, even to reverse thedirection of rotation of the controlled shaft. This continuousadjustment may be effected without interrupting the rotation, at fullspeed, of the control shaft, whether high-speed or low-speed,respectively.

The split annulus closely spaced along the circumference of thecontainer formed by the half-shells I5I and I52,

extend through the ring sections I88 and I89. A clamping cam' jaw I92 ispivotally mounted about each pivot pin I93 in the space between the ringThe clamping cam jawssections I98 and I99. I92 are therefore pivoted tothe stationary ring constituted of the ring sections I88 and I89.

A similar ring is mounted for relatable adjustment, by means of anadjusting handle I91, outside the container formed by the half-shellsI5I, and I52. It is constituted of similar ring .sections I and I9I,concentric with the respective ring sections I88 and IE9. The ringsections I90 and I9I are provided with pins I94, similar to the pivotpins I93, secured within recesses I- of the respective clamping cam jawsI92. They are held together by bolts I96 to prevent their separation,and they are held separated by spacing washers 2I2 mounted on the boltsI96. The clamping cam jaws I92 extend through a space between thehalf-shells I5I and I52 and into the space between the ring sections I90and I9I.

Upon movement of the adjusting handle I91 in the direction from thefull-line to the dottedline position of Fig. 21, the adjusting ring I98,I9I will be caused to turn in the same direction, whereupon its pins I94will engage the walls of the recesses I95 of the clamping cam jaws tocause these jaws to compress the split annulus I53. The tenon 209 willbe caused to move into 2 the mortise 2I8, in order to reduce thediameter of the annulus I53. Because the clamping cam jaws I92 areclosely spaced, this contraction of the circumference of the annulus I53 will be. even and uniform, irrespective of the degree of adjustment,so that the annulus I53 will always have the same center, in all itspositions of adjustment. Actuation of the adjusting handle I91 in theopposite direction will result in an equally uniform expansion of theannulus I53. A link 20I connects the annulus I53 with the stationaryring I88, I89 at 20I and 282 to hold it in approximately the sameposition in all conditions of I53 is shown more particu-- larly in Fig.23 as provided with a tenon 289 at I89 and I89 that are held

